An improved model of ethanol and nicotine co-use in female P rats: Effects of naltrexone, varenicline, and the selective nicotinic α6β2* antagonist r-bPiDI.

•Levels of EtOH and nicotine intake during co-use were pharmacologically relevant.•Increasing the fixed ratio (FR) requirement for nicotine increases EtOH intake during co-use.•Naltrexone decreased EtOH and water intake, but not nicotine intake during co-use.•Varenicline and r-bPiDI decreased active and inactive lever pressing for nicotine.